Although the ultimate goal is to appraise the relation of hemodynamics (blood flow patterns with all their implications) to the progress of atherosclerosis, the present research program seeks a limited goal, to understand normal response of vascular tissues to mechanical forces in a local region surrounding a chronic moderate induced stenosis. A combination of experiments and theory will focus on the ideal induced ring stenosis. The differential response of the endothelial tissues should correlate unequivocally with hemodynamic patterns. In vitro experiments will provide both calibration for the canine in vivo measurements and accuracy assessment for the approximate theoretical solutions. The results will provide a basis for defining the abnormal atherogenetic mechanisms.